Nutrition

Diet pattern matters more than any individual macro, micro, or "superfood." The most consistently validated dietary patterns for longevity — Mediterranean, MIND, DASH — share a common core: lots of plants, fish, nuts, legumes, olive oil; minimal ultra-processed food, sugar-sweetened beverages, and processed/red meat.

Nuance matters too: protein adequacy in midlife protects muscle and bone, which conflicts in some interpretations with the "low protein for longevity" mTOR narrative. Fasting helps glycemic control but does not outperform continuous calorie restriction for weight or lifespan in human RCTs.

→ For a worked example of what these principles look like on the plate: a sample longevity week — a seven-day menu that operationalises every recommendation on these pages.

What the evidence actually supports

Strong:

• Mediterranean diet pattern reduces major CVD events ~30% (PREDIMED, NEJM 2018, n=7,447) and lowers all-cause mortality across multiple cohorts. The combination of olive oil, nuts, fish, legumes, and vegetables is the most robust dietary intervention in longevity science. See Dietary patterns for Mediterranean, MIND, DASH, and Blue Zones side by side.
• MIND diet (Mediterranean + DASH hybrid emphasizing leafy greens and berries) — Morris et al. 2015 found ~53% lower Alzheimer's risk in the highest-adherence tertile.
• Sugar-sweetened beverages raise CVD, T2D, and all-cause mortality risk in dose-response fashion. See Sweeteners for what added sugar, "diet" sweeteners, and sugar alcohols (erythritol, xylitol) actually do.
• Processed meat is IARC Group 1 carcinogen; unprocessed red meat is Group 2A. Both have measurable colorectal cancer and CVD signals. The wider list of harm signals — sugar, red and processed meat, industrial seed oils, alcohol — and the things that aren't as harmful as commonly claimed live under Foods to limit.
• Adequate dietary protein in older adults preserves muscle mass, reduces sarcopenia, and improves recovery from illness/surgery. The longevity-vs-strength tension — and why blanket "low protein extends life" advice misreads the midlife and older-adult evidence — is covered under Protein, mTOR, AMPK.
• Habitual fermented dairy (yogurt, kefir, traditionally aged cheese) — the most consistent fermented-food signal in pooled cohorts; lower CVD, lower all-cause mortality. See Fermented foods for why the food matrix matters more than live CFU counts.
• Ultra-processed food carries the single largest harm signal in modern nutrition science, with a ~10% mortality rise per 10% of calories from UPF and a 2025 UCL randomised feeding trial confirming the harm persists when nutrients are matched. See Ultra-processed food.

Moderate:

• Time-restricted eating with an early eating window (last meal before 17:00–19:00) improves fasting insulin and body composition more than late eating, even when calories are matched. The full intermittent-fasting / alternate-day / fasting-mimicking landscape is covered under Fasting.
• Fasting and continuous calorie restriction produce similar weight loss and metabolic improvements long-term (Cochrane 2026; BMJ 2025 network meta-analysis n=6,582).
• High polyphenol intake (berries, olive oil, dark chocolate, tea, herbs) — observational signal for vascular and cognitive outcomes; mechanism plausible.
• Postprandial glucose control matters even in healthy non-diabetics; continuous glucose monitoring has revealed individual "glucotypes" and a toolkit — sequencing, sourdough, vinegar, chrononutrition — that flattens the curve without cutting carbs. See Glycemic index. The related capacity to switch fuels between glucose and fat — metabolic flexibility — is itself an aging-resilience marker.
• GLP-1 receptor agonists (semaglutide / tirzepatide) — for adults with overweight/obesity or cardiometabolic risk: durable double-digit weight loss, 20% MACE reduction, and the first drug class to measurably slow validated epigenetic aging clocks. The catch: muscle and bone loss without aggressive protein and resistance training. See GLP-1 receptor agonists.

Weak / preliminary:

• "Optimal" macronutrient ratios — wide ranges are compatible with longevity if the food quality is high.
• Many specific superfoods (turmeric, açaí, etc.) have animal/mechanistic data without robust human RCTs.

Practical nutrition principles (evidence-weighted)

1. Default to a Mediterranean pattern. Vegetables, legumes, fish, nuts, olive oil, whole grains, fruit. Optional moderate dairy (yogurt, cheese), modest poultry. This is the single most-evidenced dietary intervention.
2. Eat fish 2+ times/week (especially fatty fish: salmon, sardines, mackerel) or take EPA+DHA omega-3 if not.
3. Hit protein targets. ~1.2–1.6 g/kg/day for active midlife adults; older adults probably benefit from upper end. Distribute across meals (~30–40 g per meal).
4. Limit added sugar to <10% of calories (WHO) or <25 g/day (AHA for women).
5. Limit ultra-processed food (full article). The clearest dose-response signal in modern nutrition; each 10% increase in UPF energy associates with ~10% higher all-cause mortality. The 2025 UCL randomised feeding trial confirmed processing harms persist even when calories and nutrients are matched.
6. Limit red meat to 1–3 servings/week; minimize processed meat. Replace with fish, legumes, poultry.
7. Eat fiber — 25–35 g/day. Strongest single nutrient signal for cardiovascular and colorectal cancer prevention.
8. Front-load eating. Larger breakfast/lunch, lighter dinner, last meal 2–3 hours before bed. Aligns with circadian biology.
9. Don't smoke; drink minimally; hydrate adequately.

→ See a sample longevity week for a concrete 7-day menu that hits the protein, fibre, fish, legume, fermented-food, and meal-sequencing targets simultaneously, with notes for older-adult, GLP-1, training, and vegetarian/vegan variants.

What's overhyped

• Carnivore, ketogenic, and zero-carb diets for general longevity — short-term metabolic improvements in some populations; long-term outcomes data are absent or unfavorable.
• "Detoxes" and cleanses — no clinical evidence for benefit; the liver and kidneys handle this.
• Specific superfoods marketed for individual health claims — diversity beats specialization.
• Most "anti-inflammatory diet" supplement protocols — anti-inflammatory eating works through the pattern, not concentrated extracts.

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